Preliminary studies on the mid-infrared analysis of edible oils by direct heating on an ATR diamond crystal

In this work a new, easy and rapid MIR-ATR technique to monitor the thermal stability of oils is presented. The method uses a heated ATR apparatus set at selected temperatures to thermally modify the oils and simultaneously acquire spectra. Because of the larger sample surface to volume ratio, degradation reactions are faster compared to other heating methods. Three different edible oils (sunflower, olive and canola), are subjected to the method. Sunflower oil with or without tocopherol and at three different temperatures (130, 150 and 170 °C) was also analysed. Wavenumbers known to be relevant to oil degradation processes are selected to show the modifications in the spectra over time.     

Evaluation of the Performance of a Portable Mid-Infrared Analyzer for the Rapid Determination of Total Trans Fat in Fast Food

The performance of a novel, transmission‐mode, portable, Fourier transform infrared (FTIR) analyzer was evaluated and compared to that of a benchtop attenuated total reflection (ATR)‐FTIR spectrometer. The total concentration of trans fatty acids in the fat extracted from 19 representative fast foods was rapidly (<5 min) quantified in a single measurement after conversion to fatty acid methyl esters (FAME). While the FTIR determination is rapid, the time required for extraction and derivatization is not. For all extracts, the total trans FAME concentration varied from approximately 0.5 to 11 % (of total FAME) as determined using the portable FTIR analyzer. The trans fat contents (mean ± SD), expressed in grams per serving and calculated on the basis of total fat content and FTIR determination of trans fat content, were found to be 1.00 ± 0.42 for hamburgers, 0.67 ± 0.78 for chicken tenders, 1.00 ± 1.24 for French fries, and 0.27 ± 0.23 for apple pies. Determinations of total trans‐unsaturated FAME were consistent with those obtained by use of ATR‐FTIR and GC official methods (AOCS Cd 14e‐09 and AOCS Ce 1j‐07, respectively). These results indicate that the portable FTIR analyzer is suitable for the rapid and routine quantification of total trans fat measured as FAME prepared from fats extracted from fast foods.     

A review of the features and analyses of the solid electrolyte interphase in Li-ion batteries

The solid electrolyte interphase (SEI) is a protecting layer formed on the negative electrode of Li-ion batteries as a result of electrolyte decomposition, mainly during the first cycle. Battery performance, irreversible charge “loss”, rate capability, cyclability, exfoliation of graphite and safety are highly dependent on the quality of the SEI. Therefore, understanding the actual nature and composition of SEI is of prime interest. If the chemistry of the SEI formation and the manner in which each component affects battery performance are understood, SEI could be tuned to improve battery performance. In this paper key points related to the nature, formation, and features of the SEI formed on carbon negative electrodes are discussed. SEI has been analyzed by various analytical techniques amongst which FTIR and XPS are most widely used. FTIR and XPS data of SEI and its components as published by many research groups are compiled in tables for getting a global picture of what is known about the SEI. This article shall serve as a handy reference as well as a starting point for research related to SEI.     

Fourier Transform Infrared Spectroscopy for Kona Coffee Authentication

ABSTRACT:  Kona coffee, the variety of "Kona typica" grown in the north and south districts of Kona-Island, carries a unique stamp of the region of Big Island of Hawaii, U.S.A. The excellent quality of Kona coffee makes it among the best coffee products in the world. Fourier transform infrared (FTIR) spectroscopy integrated with an attenuated total reflectance (ATR) accessory and multivariate analysis was used for qualitative and quantitative analysis of ground and brewed Kona coffee and blends made with Kona coffee. The calibration set of Kona coffee consisted of 10 different blends of Kona-grown original coffee mixture from 14 different farms in Hawaii and a non-Kona-grown original coffee mixture from 3 different sampling sites in Hawaii. Derivative transformations (1st and 2nd), mathematical enhancements such as mean centering and variance scaling, multivariate regressions by partial least square (PLS), and principal components regression (PCR) were implemented to develop and enhance the calibration model. The calibration model was successfully validated using 9 synthetic blend sets of 100% Kona coffee mixture and its adulterant, 100% non-Kona coffee mixture. There were distinct peak variations of ground and brewed coffee blends in the spectral "fingerprint" region between 800 and 1900 cm⁻¹. The PLS-2nd derivative calibration model based on brewed Kona coffee with mean centering data processing showed the highest degree of accuracy with the lowest standard error of calibration value of 0.81 and the highest R ² value of 0.999. The model was further validated by quantitative analysis of commercial Kona coffee blends. Results demonstrate that FTIR can be a rapid alternative to authenticate Kona coffee, which only needs very quick and simple sample preparations.     

Improved adhesion of poly(tetrafluoroethylene) by NH3-plasma treatment

—Surface modification of poly(tetrafluor oethylene) (PTFE) by NH₃-plasma treatment was investigated by means of contact angle measurement, XPS, and ATR FT/IR spectroscopy. The modified surfaces were adhesively bonded to nitril rubber. The NH₃-plasma irradiation made PTFE surfaces hydrophilic. The contact angle of water on the modified PTFE surface was 16 deg, and the surface energy was 62-63 mJ/m². The NH₃-plasma irradiation improved adhesion between PTFE and nitril rubber using a phenol-type adhesive. The peel strength of the joints reached 8.1 × 10³ N/m. Carbonyl and amido groups were created on PTFE surfaces by the NH₃-plasma irradiation. The mechanism of the improvement of adhesion by the NH₃-plasma irradiation is discussed.     

利用Dempster—Shafer信息融合进行自动目标识别

本文主要对红外图像中铁路的特点,将图像处理技术与人工智能相接合,提出一种基于知识的智能识别方法。采用先建立完善的知识特征集,再以知识特征集为基础,采用Dempster-Sgafer来对特征集进行融合来识别铁路枢纽。其基本思路可用作一般目标识别。     

ATR信息处理的软件体系结构

为解决雷达自动目标识别设计中的整体设计框架问题,从ATR系统的特点出发,采用领域工程的分析方法对大量的ATR系统进行了系统化分析,在此基础上构建了基于代数学的构件模型,并给出ATR系统的模型.该模型作为ATR支撑平台开发的基础,支持ATR系统的快速开发.理论分析表明:该模型支持插头插座式的软件体系结构,为开放式ATR支撑平台提供了理论基础,为后续的ATR系统建模提供了构件模型规范,同时为ATR构件库的创建提供了支撑.     

利用组播技术解决远程数据传输中的网络拥塞问题

计算机网络与通信技术的发展，为雷达目标及环境特性数据的获取与传输手段的改进提供了技术支持，但由于传输速度与网络带宽的限制，因此在现实应用中还没有很好的效果，该文根据实际雷达目标识别系统的需求，引入计算机网络中的组播技术，对网络中的数据流量进行控制，较好地解决了网络拥塞问题，为远程的实时目标及环境特性数据应用于目标识别系统扫除了障碍。     

基于EFI上的USIM设备驱动程序开发

以USIM驱动程序的开发为例,论述了EFI下设备驱动程序开发的过程,包括EFI驱动模式技术的使用,USIM中ATR数据的解析, APDU命令／数据包的接收和发送,以及两种USIM通信协议的实现。     

一种自适应的合成孔径雷达图像目标检测方法

目标检测是自动目标识别的一个重要步骤,论文提出了一种自适应的SAR图像目标检测方法,该方法采用基于Weibull分布模型的恒虚警率(CFAR)检测技术,将参考窗口分块,判断各子块类型,根据各子块类型不同,自适应选择参考样本确定阈值。在检测过程中,利用灰度和方差特征,预先排除明显不为目标的像素。对CFAR检测结果,利用目标基本形状特征排除虚警。实验证明,该方法在同质区和非同质区背景下都具有较好的检测性能。